import { router, Stack, useLocalSearchParams } from "expo-router";
import { Pressable, ScrollView, StyleSheet, Text, View } from "react-native";

import { AppBackground } from "@/components/AppBackground";
import { LoadingScreen } from "@/components/LoadingScreen";
import { StatusBadge } from "@/components/StatusBadge";
import { Button } from "@/components/ui/Button";
import { Card } from "@/components/ui/Card";
import { fonts, spacing } from "@/constants/theme";
import { useAppTheme } from "@/contexts/ThemeContext";
import { formatCurrency, formatDate } from "@/lib/format";
import { getInvoiceStatus } from "@/lib/invoice-status";
import { useTabBarScrollPadding } from "@/lib/tab-bar-insets";
import type { ThemeColors } from "@/lib/theme-palette";
import { useThemedStyles } from "@/lib/use-themed-styles";
import { api } from "@/lib/trpc";

export default function ClientDetailScreen() {
  const { colors } = useAppTheme();
  const styles = useThemedStyles(createClientDetailStyles);
  const { id } = useLocalSearchParams<{ id: string }>();
  const scrollPadding = useTabBarScrollPadding();

  const clientQuery = api.clients.getById.useQuery(
    { id: id ?? "" },
    { enabled: Boolean(id) },
  );

  if (!id) {
    return <LoadingScreen message="Invalid client" />;
  }

  if (clientQuery.isLoading) {
    return <LoadingScreen message="Loading client…" />;
  }

  const client = clientQuery.data;
  if (!client) {
    return <LoadingScreen message="Client not found" />;
  }

  const invoices = client.invoices ?? [];
  const totalInvoiced = invoices.reduce((sum, invoice) => sum + invoice.totalAmount, 0);
  const currency = client.currency ?? "USD";

  return (
    <AppBackground>
      <Stack.Screen options={{ headerBackTitle: "Entities" }} />
      <ScrollView
        contentContainerStyle={[styles.container, { paddingBottom: scrollPadding }]}
        contentInsetAdjustmentBehavior="automatic"
        scrollIndicatorInsets={{ bottom: scrollPadding }}
      >
        <View style={styles.hero}>
          <Text style={styles.name}>{client.name}</Text>
          {client.email ? <Text style={styles.meta}>{client.email}</Text> : null}
          {client.phone ? <Text style={styles.meta}>{client.phone}</Text> : null}
        </View>

        <Card title="Summary">
          <DetailRow label="Total invoiced" value={formatCurrency(totalInvoiced, currency)} />
          <DetailRow label="Invoices" value={String(invoices.length)} />
          {client.defaultHourlyRate != null ? (
            <DetailRow
              label="Default rate"
              value={`${formatCurrency(client.defaultHourlyRate, currency)}/hr`}
            />
          ) : null}
        </Card>

        {(client.addressLine1 || client.city || client.state) && (
          <Card title="Address">
            {client.addressLine1 ? <Text style={styles.body}>{client.addressLine1}</Text> : null}
            {client.addressLine2 ? <Text style={styles.body}>{client.addressLine2}</Text> : null}
            {(client.city || client.state || client.postalCode) && (
              <Text style={styles.body}>
                {[client.city, client.state, client.postalCode].filter(Boolean).join(", ")}
              </Text>
            )}
            {client.country ? <Text style={styles.body}>{client.country}</Text> : null}
          </Card>
        )}

        <Card title="Invoices">
          {invoices.length === 0 ? (
            <Text style={styles.muted}>No invoices for this client yet.</Text>
          ) : (
            invoices.map((invoice) => {
              const status = getInvoiceStatus(invoice);
              return (
                <Pressable
                  key={invoice.id}
                  style={styles.invoiceRow}
                  onPress={() => router.push(`/(app)/invoices/${invoice.id}`)}
                >
                  <View style={styles.invoiceMeta}>
                    <Text style={styles.invoiceTitle}>
                      {invoice.invoicePrefix}
                      {invoice.invoiceNumber}
                    </Text>
                    <Text style={styles.muted}>Due {formatDate(invoice.dueDate)}</Text>
                  </View>
                  <View style={styles.invoiceRight}>
                    <Text style={styles.invoiceAmount}>
                      {formatCurrency(invoice.totalAmount, invoice.currency)}
                    </Text>
                    <StatusBadge status={status} />
                  </View>
                </Pressable>
              );
            })
          )}
        </Card>

        <View style={styles.actions}>
          <Button
            title="Edit client"
            onPress={() => router.push(`/(app)/entities/clients/edit/${client.id}`)}
          />
          <Button
            title="New invoice"
            variant="secondary"
            onPress={() => router.push("/(app)/invoices/new")}
          />
        </View>
      </ScrollView>
    </AppBackground>
  );
}

function DetailRow({ label, value }: { label: string; value: string }) {
  const { colors } = useAppTheme();
  return (
    <View style={detailStyles.row}>
      <Text style={[detailStyles.label, { color: colors.mutedForeground }]}>{label}</Text>
      <Text style={[detailStyles.value, { color: colors.foreground }]}>{value}</Text>
    </View>
  );
}

const detailStyles = StyleSheet.create({
  row: {
    flexDirection: "row",
    justifyContent: "space-between",
    alignItems: "center",
    paddingVertical: 4,
  },
  label: {
    fontFamily: fonts.body,
    fontSize: 14,
  },
  value: {
    fontFamily: fonts.bodySemiBold,
    fontSize: 14,
  },
});

const createClientDetailStyles = (colors: ThemeColors, _isDark: boolean) =>
  StyleSheet.create({
    container: {
      padding: spacing.md,
      gap: spacing.md,
    },
    hero: {
      gap: 4,
    },
    name: {
      fontSize: 24,
      lineHeight: 28,
      fontFamily: fonts.heading,
      color: colors.foreground,
    },
    meta: {
      fontSize: 14,
      fontFamily: fonts.body,
      color: colors.mutedForeground,
    },
    body: {
      fontFamily: fonts.body,
      fontSize: 14,
      color: colors.foreground,
      lineHeight: 20,
    },
    muted: {
      fontFamily: fonts.body,
      fontSize: 14,
      color: colors.mutedForeground,
    },
    invoiceRow: {
      flexDirection: "row",
      justifyContent: "space-between",
      gap: spacing.md,
      paddingVertical: spacing.sm,
      borderTopWidth: 1,
      borderTopColor: colors.border,
    },
    invoiceMeta: {
      flex: 1,
      gap: 2,
    },
    invoiceTitle: {
      fontFamily: fonts.bodySemiBold,
      color: colors.foreground,
      fontSize: 15,
    },
    invoiceRight: {
      alignItems: "flex-end",
      gap: spacing.sm,
    },
    invoiceAmount: {
      fontFamily: fonts.bodySemiBold,
      color: colors.foreground,
      fontSize: 15,
    },
    actions: {
      gap: spacing.sm,
    },
  });